One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,7)(5,8)(9,10)(11,18)(12,21)(13,22)(14,16)(15,17)(19,20)(23,24)(25,26,30,34)(27,29,33,31)(28,32,37,40)(35,36,39,38)(3,8)(5,6)(9,11,15,14)(10,16,17,18)(12,19,22,24)(13,20,21,23)(25,27)(26,31)(28,35)(29,34)(30,33)(32,38)(36,40)(37,39)(1,3)(2,5)(4,8)(6,7)(25,26)(27,31)(28,32)(29,33)(30,34)(35,38)(36,39)(37,40) involution — undirected(1,3)(2,6)(4,8)(5,7)(9,12)(10,13)(11,19)(14,24)(15,22)(16,20)(17,21)(18,23)(25,26)(27,29)(28,32)(30,34)(31,33)(35,36)(37,40)(38,39) involution — undirected(9,13)(10,12)(11,20)(14,23)(15,21)(16,19)(17,22)(18,24)(25,28,30,37)(26,32,34,40)(27,35,33,39)(29,36,31,38)(1,2)(3,5)(4,7)(6,8)(9,14,15,11)(10,16,17,18)(12,19,22,24)(13,23,21,20)(25,29)(26,33)(27,34)(28,36)(30,31)(32,39)(35,40)(37,38)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.